Exam (elaborations) WGU BioChemistry C785 Exam Review 170/WGU BioChemistry C785 Exam Review 170 (Q/A) Latest 2022

1. Match the letters with the correct names of the processes of the central dogma (Replication; Transcription; Translation). A) Replication, B) Transcription, C) Translation 2. Label the lettered strands of nucleic acid below. The possible words to use in labeling strands are: Coding Strand, Non- template Strand, Non-coding Strand, Template Strand, and mRNA. Note: A and B refer to one strand of DNA; C and D refer to the other strand of DNA. A) Non-template B) Coding C) Template D) Non-coding E) mRNA 3. If one strand of chromosome 2 has a DNA sequence that consists of this: 5’ AAG CGG TAC GTA 3’ What will be the composition of the complementary DNA strand? (Select all that apply) 3' TTC GCC ATG CAT 5' & 5'TAC GTA CCG CTT 3' 4. During DNA replication, which of the following sequences can be used as a primer for the following DNA sequence: 3' AGT GGA TCA CTA GGC TCT 5'? (Recall that DNA replication uses RNA primers whereas PCR uses DNA primers). 5' UCA CCU AGU GAU 3' 5. Which of the following is the correct tRNA anticodon for the mRNA codon 5' GCA 3' ? 5' UGC 3' 6. The following sequence is the coding DNA strand of the collagen gene: 5’ ATG GCG TTC GAA 3’ What is the sequence of the corresponding mRNA? 5' AUG GCG UUC GAA 3' 7. What would be the resulting mRNA sequence from a template strand with this sequence: 5’-CAG CTC GTC-3’? 5’-GAC GAG CUG-3’ 8. What is the coding strand sequence if the non-template strand sequence is 5’-AGC CTT TAA CTA-3’ 3’-ATC AAT TTC CGA-5’ 9. What would be the amino acid sequence that would result from this template sequence: 5'-TGC AAG CCA-3’? Trp Leu Ala 10. What would the amino acid sequence be from this coding strand sequence: 5’-GGA AGG CCC-3’ (utilize the table from question 9)? Gly Arg Pro 11. A mutation in the DNA that changes the sequence of a codon but does NOT change the amino acid sequence of the protein describes a _____ _____. silent mutation. 12. A nonsense mutation changes a codon to introduce a premature stop codon 13. Point mutations change a single nucleotide in a mutant gene compared to the normal gene. Examples are missense, nonsense, and silent mutations. 14. A missense mutation changes a single amino acid in a protein. 15. Frameshift mutations change the number of nucleotides in a mutant gene compared to the normal gene. Examples are insertion and deletion mutations. 16. When comparing a normal and mutant gene sequence, how do you identify a frameshift mutation? The number of nucleotides between the normal and mutant gene sequences is different and the amino acid sequence is different. 17. If the coding (non-template) DNA sequence of a normal gene is 5' GTC GCA TGG TGA 3', what kind of mutation would create the mutant gene sequence 5' GTC GAC ATG GTG A 3'? Insertion mutation 18. If the coding (non-template) DNA sequence of a normal gene is 5' GTC GCA TGG TGA 3', which DNA sequence would represent a nonsense mutation (utilize table from question 17)? 5' GTC GCA TAG TGA 3' 19. If the coding (non-template) DNA sequence of a normal gene is 5' GTC GCA TGG TGA 3', which DNA sequence would represent a deletion mutation (utilize table from question 17)? 5' GTC GCA TGT GA 3' 20. Which of the following would be considered a point mutation to a DNA strand that consists of a nucleotide sequence: 5’ CTG ACG TAT CTT AAT 3’ (utilize table from question 17)? 5’ CTG ACG TAA CTT AAT 3’ 21. The RNA sequence 5’-CUC AUA GCC UGA CCC-3’ is mutated to 5’-CUC AUA GCC UAA CCC-3’ What kind of mutation is this? (utilize table from question 17) Silent 22. 12. The following is the mRNA sequence for actin, a protein that provides structure to a cell: 5’ ACU AGA CGU UUU UAA 3’. A mutation to the actin gene results in the production of the following mRNA: 5’ ACU AGA CAU UUU UAA 3’ What type of mutation is this? (utilize table from question 17) Missense 23. Sickle Cell Anemia is inherited in an autosomal recessive pattern. Choose the set of chromosomes of a person that has inherited the disease. Green boxes represent normal alleles and yellow boxes represent mutant alleles. D 24. Hemophilia is an X-linked recessive condition. This means that: A person with at least one normal X chromosome without the hemophilia gene will not show signs of hemophilia 25. A woman is homozygous for an abnormal allele on Chromosome 2 that codes for an autosomal dominant disease. This means that she: Will have the disease 26. Mutations in the FANCA gene (located on chromosome 16) can lead to Fanconi Anemia. A healthy individual inherited one mutant and one normal allele of the FANCA gene. Which of the following describes the inheritance pattern of Fanconi Anemia? Autosomal Recessive 27. A black female mouse mates with a white male mouse and produces a litter of all gray mice. Which inheritance pattern can be used to describe this situation? Incomplete Dominance 28. Two healthy individuals give birth to a child that has Bloom Syndrome. From this information, it can be concluded that Bloom syndrome is inherited in a ________ manner. Recessive 29. Both pedigrees show the inheritance of von Willebrand disease, a bleeding disorder in which platelets fail to clot properly. There are different types of von Willebrand disease that exhibit different inheritance patterns. Type I is inherited in an autosomal dominant fashion, while type III is autosomal recessive. Which of the following statements best describes the families depicted in the pedigrees below? Family 1 has type III and Family 2 has type I 30. What is the expected probability that a child will have an autosomal dominant disease if their father is heterozygous for the allele and their mother is homozygous for the normal allele? 50% 31. Craniofrontonasal Dysplasia is an X-linked Dominant disorder. This condition is very rare and is caused by mutations in the Ephrin B-1 gene. Which one of the following pedigrees portrays the familial inheritance pattern of this X-linked Dominant disorder? 32. The Punnett Squares below represent three different types of dominance. Which answer choice correctly identifies the different types of Dominance? A. Incomplete Dominance; B. Complete Dominance; C. Codominance 33. Proteins that promote coiling of DNA and help prevent DNA strands from "tangling" are called? Histones 34. Epigenetics. Given the following modification of the nucleosomes, discuss how the transcription and gene expression is impacted. In A the the nucleosomes are less condensed, and in B they are more tightly wound. Would A or B foster the ability to have more active transcription of genes? A 35. Some changes to the DNA do not modify the coding sequence of the DNA but do affect its winding and unwinding from nucleosomes. These changes can increase or decrease the availability of DNA and hence, the transcription of a gene. These are called _________ changes? Epigenetics 36. Select all of the following that are involved in the process of actively transcribing a gene. Epigenetic modifications to nucleosomes, Transcription Factors, Promoters, RNA polymerase 37. What changes can occur to the DNA (ex. methyl groups) and to the histones that will impact gene expression? Select all that apply Methylation, Acetylation 38. Which of the following statements about epigenetics is false? The DNA sequence is permanently altered. 39. The LCT gene codes for Lactase, which is responsible for the breakdown of lactose. Which of the following statements could explain how Lactase activity is increased in the presence of lactose? The presence of lactose causes nucleosomes to separate, exposing the LCT gene 40. Histone proteins can be chemically modified by addition of an methyl group. If this causes nucleosomes to pack _________ , the process of ___________ is decreased at those DNA sites. More tightly; transcription 41. The LEP gene codes for an anorexigenic hormone. Interestingly, breastfeeding has been shown to alter methylation of the promoter of this gene, leading to increased LEP expression. What is likely happening in response to breastfeeding: Breastfeeding decreases the methylation of the promoter of the LEP gene, increasing the spacing between nucleosomes. 42. In the organization of DNA into chromosomes, DNA is wrapped around _________ to form nucleosomes. Nucleosomes are organized further to form _____________. Histones; Chromatin 43. Base excision repair: Fixes single damaged nucleotides 44. Nucleotide excision repair Fixes multiple damaged nucleotides 45. Mismatch repair Fixes mistakes made by DNA polymerase during DNA replication 46. Homologous recombination: Repairs a broken chromosome using genetic information from same chromosome inherited from other parent. 47. When the wrong nucleotide is added to a newly forming DNA strand during DNA replication Distortion of the double helix structure occurs because of uncomplimentary pairing of the nucleotides 48. A patient with xeroderma pigmentosum is prone to developing multiple skin cancers starting in childhood. This occurs because of a mutation in a gene that codes for enzymes that help repair DNA damage through the nucleotide excision repair (NER) pathways. How does NER differ from other repair mechanisms? In NER: The error in one strand of DNA is removed as well as several nucleotides on either side of the error. The gap that was removed is filled in by DNA polymerase 49. Which of the following is NOT a step in base excision repair? Synthesis of an RNA primer 50. Several components of cigarette smoke, including benzopyrene, insert themselves (intercalate) into the DNA and lead to several types of mutations such as frameshift mutations, including both insertions and deletion. Which of the following repair pathways would be used to repair this type of damage? Nucleotide Excision Repair 51. What is the proper order of the steps involved in excision repair? Recognize the damage, remove the damage, resynthesize the sequence, ligate the DNA backbone 52. Which statement is true with respect to mismatch repair and nucleotide excision repair (NER)? Mismatch repair follows the same steps are NER 53. True or False: The polymerase chain reaction is a tool used to study protein structure. False 54. What color is the primer in the following diagram? Red 55. True or False: dNTPs are DNA nucleotides used in PCR True 56. True or False: A thermocycler is a machine used for PCR that varies the temperature of a sample True 57. True or False: DNA polymerase is used in DNA replication and in PCR True 58. Which of the following changes can NOT be detected using PCR? Epigenetics changes 59. Which of the following components is NOT used for PCR? RNA polymerase 60. Assuming there is one copy of the target DNA sequence before PCR, how many copies of DNA are there after 5 PCR cycles? 32 61. DNA polymerase can synthesize new DNA strands in which direction? 5’ to 3’ 62. The following are steps involved in a polymerase chain reaction. Which is the correct order: Denaturation, annealing, and elongation 63. Choose the answer that correctly lables the amno group, the carboxyl group and the variable group in the amino acid below: A Variable group, B Amino Group C Carboxyl Group 64. Which characteristic correctly describes the amino acid shown below? Non-polar (R groups w CH…polar r groups w SH, NH, OH, CN, or C=O…charged r groups that are + or -) 65. What bonds can the R group of the amino acid form to stabilize tertiary structure? Hydrogen bonds & Disulfide Bonds 66. What kind of interaction can the following pair of amino acids form between their side chains (R-groups)? Hydrogen Bonds 67. A missense mutation resulting in a change from asparagine to leucine at a specific position on an enzyme leads to a neurodegenerative disease. Is there an alternate amino acid substitution of a missense mutation listed below that would have less of an impact on the protein structure and consequently its function than the proposed leucine substitution would? 68. Which of the following interactions can occur between two positively charged amino acids? None of these (no bonds can occur between two positively charged amino acids) 69. Antibodies that enable our body to fight bacterial infections must bind to antigens on the surface of the bacterial cell. If the antigen on the surface of the bacterial cell has several negatively charged amino acids, which of the following amino acids would you expect to find on the portion of the antibody that binds to the antigen? 70. What category does this amino acid belong to? Charged 71. True or False: This amino acid is polar True 72. True or False: This amino acid would prefer to interact with oil over water False 73. Which of the following best describes the nature of protein primary structure? Amino acids linked together in a specific order by peptide bonds 74. Which of the following statements about the different levels of protein structure is true? The interactions between the side chains of the amino acids make up the tertiary level structure of a protein 75. Which type of bonding or interaction is correctly paired with a chemical or change in environment that will disrupt/break the interaction or bond? Hydrogen bonds/ionic bonds: Change in pH 76. Which of the following statements about protein structure and stability is true? Ionic bonds between the side chains of the charged amino acids stabilize the protein structure The negatively charged amino acid, Glutamate, is replaced with the negatively charged amino acid Aspartate. 77. Which level of protein structure is most significantly impacted by this change? Primary Structure 78. Which of the following pairs of amino acids are NOT likely to interact with one another to stabilize tertiary structure? Side-chains of the aspartate and the glutamate are both negatively changed, So they will repel each other (opposites attract, like charges repel) 79. Which portion of the amino acid below is likely to engage in a hydrogen bond with an oxygen in the carboxyl group of another amino acid as part of a beta pleated sheet? A 80. Primary structure consists of the order of ______ in a protein. These are held together with ______ bonds that are formed by a ______ reaction. Amino acids, peptide, dehydration 81. Which of the following statements about the secondary structure of proteins is true? You may select more than one answer. It involves hydrogen bonding between the backbone atoms & It includes alpha helices as a common form. & It includes beta pleated sheets as a common form. 82. What type of reaction breaks peptide bonds apart? Hydrolysis Reactions 83. Glutamine at position 16 forms an important interaction with Serine in a different location in the protein. How would the protein structure be affected if the Glutamine in position 16 were mutated to Leucine? Would this increase or decrease the stability of the protein? 84. Decrease. Serine and Leucine do not interact Decrease. Glutamine and Serine formed a hydrogen bond that stabilized the protein structure before the mutation 85. When Estrogen binds to the binding pocket of the Estrogen Receptor, it is stabilized by hydrogen bonds. Which amino acids listed below could stabilize the interaction with Estrogen in the binding pocket of the Estrogen Receptor? Check all that apply. Amino Acid 16 86. The amino acid at position 150 (not shown) helps to stabilize the protein by forming disulfide bonds. What amino acid is likely located at position 150? Could this amino acid form a disulfide bond with any of the amino acids in the provided sequence above? 87. If all of the Arginine amino acids (position 2, 5, 6, 9 and 15) in the sequence above are mutated to Lysine, would there be a significant effect on the protein’s stability? No, not significant, Lysine and Arginine would have all the same interactions 88. Aggregation of proteins is the main reason behind many neurodegenerative diseases. Which one of the following mutations will likely cause a neurodegenerative disease? Replacing a polar amino acid with a non polar amino acid 89. A mutation in the protein A gene results in a negatively charged amino acid, Glutamate, being replaced with the nonpolar amino acid Leucine. This is an example of a _______ mutation that could potentially interrupt __________. missense, an ionic bond 90. Diabetic ketoacidosis can lower blood pH, which affects the structure of important proteins like hemoglobin. Which of the following interactions are most likely affected by the change in pH? Choose the letter(s) corresponding to the interaction. A & B 91. In order to fulfill their function, proteins must fold in proper, three-dimensional conformations. Which one of the following molecules, available in a cell, is likely to help a protein fold properly? Chaperone 92. Alzheimer disease is caused by aggregation of the Amyloid beta peptide and tangle formation by the tau protein. What kinds of amino acids are likely to drive the formation of these protein aggregates? Hydrophobic 93. As a piece of bacon is heated in a skillet on the stove, you observe that the appearance of the bacon changes. You may even notice that the bacon becomes crispy if left in the skillet. What type of bonds or interactions in proteins are susceptible to temperature changes? Why? Hydrophobic interactions. As the temperature increases, as it does in the skillet, the atoms in the proteins in bacon begin to move more rapidly. This causes the hydrophobic areas of the protein to become exposed. 94. A toddler mistakenly swallows a bathroom cleaning solution, containing a strong reducing agent. Which interaction is most likely to be disrupted within a glycoprotein in the lining of the toddlerʼs esophagus? Disulfide Bond 95. A patient presents with a fever of 110°F. Which interaction(s) would be disrupted within a neuronal protein if the fever is not resolved quickly. Hydrophobic Interactions 96. A diabetic patient is suffering from ketoacidosis. Which interaction(s) could be disrupted within the patientʼs hemoglobin due to this condition. (Click all that apply) Hydrogen Bond & Ionic Bonds 97. Which of the following forces can lead to aggregation as a result of protein misfolding? Hydrophobic Interactions 98. Which of the following interactions involve a covalent bond? (check all that apply) Peptide Bond & Disulfide Bond 99. The two amino acids below are part of the myosin protein. What interaction can these amino acids form, and where are they likely to be located in the protein? Hydrophobic interaction, the core of the protein 100. Which of the following are true about a misfolded protein? You may select more than one answer. It will lose its normal function; it can be degraded by the cell; it can be the result of denaturation; it can cause protein aggregation 101. Which of the following amino acids would you expect to find in the interior of a protein rather than on its exterior? 102. As a piece of bacon is heated in a skillet on the stove, you observe that the appearance of the bacon changes. You may even notice that the bacon becomes crispy if left in the skillet. What types of bonds or interactions in proteins are susceptible to temperature changes? Hydrophobic Interactions 103. 10. If lysine is required at position #150 in the peptide chain in order for a protein to properly fold and function, what happens if amino acid #150 is mutated from lysine to alanine? (The structures of lysine and alanine are provided below.) The protein will not fold properly 104. Using the hypothetical pathway, which molecule would accumulate if Enzyme Y stopped working? Triangle 105. Using the hypothetical pathway, which molecule would decrease if Enzyme Z stopped working (utilize chart from question 104)? Star 106. Using the hypothetical pathway, which downstream product could inhibit Enzyme X due to feedback inhibition (utilize chart from question 104)? Star 107. For the pathway below, which of the following statements is true? Molecule C inhibits Enzyme 3 108. Below is a depiction of the enzyme cycle for sucrase. Which of the following is true. Sucrose is the substrate of sucrase 109. The diagram on the left illustrates the pathway that synthesizes isoleucine. When isoleucine levels drop, how would you describe the activity of threonine deaminase? Its activity is high since feedback inhibition is relieved 110. Which enzyme is F likely to inhibit and what type of inhibitor is it? Enzyme 1, competitive inhibitor 111. When inhibitor F is present, which best describes what will happen to enzyme 2(utilize image from 111)? The inhibition of the enzyme 2 will be relieved 112. If enzyme 2 was defective, the amount of B would ________ while the amount of C would ____ Increase, decrease 113. If molecule D acts as a feedback inhibitor for enzyme 1 in this pathway, what happens to the amount of molecule A following initiation of feedback inhibition (utilize image from question 112)? Increase 114. Which one of the following paths requires less activation energy to convert the reactants into the products? The options include the path indicated by a bold line, and the path indicated by a dotted line. In presence of an enzyme-Dotted line 115. Select True or False: the lower the activation energy for a reaction, the faster the reaction rate True 116. How do enzymes eliminate the need for high temperatures to complete a reaction? The need for high temperatures is eliminated by lowering the activation energy needed for the reaction 117. 4.) An enzyme that adds a phosphate group is a __________. An enzyme that removes a phosphate group is known as a _____________________. Kinase, phosphatase 118. Which level of protein structure provides enzymes with their substrate specificity? Tertiary structure 119. Which of the following are characteristics of enzymes? (select all that apply) They are reusable, They speed up a reaction, They catalyze a specific type of reaction 120. A substrate binds to an enzyme at a specific site, which is referred to as a(n)_________________. Active site 121. Which of the following factors can affect the protein folding and activity of an enzyme? All of the options are correct (Heat, pH, and Reducing agents) 122. Which of the following are possible effect(s) that phosphorylation/dephosphorylation can have on the activity of an enzyme? Select all that apply. Turn the enzyme “off” 123. Induced fit describes which of the following? An enzyme slightly changes its shape to accommodate specific substrates 124. Phenylalanine hydroxylase is an enzyme that breaks down phenylalanine in the body. When there are low levels of this enzyme, as seen in Phenylketonuria, what is the consequence? Phenylalanine levels increase 125. Phenylalanine is toxic to the developing brain. Using the following schematic, propose a suggestion to alleviate the problems associated with Phenylketonuria (utilize the image from 124) Increase activity of phenylalanine hydroxylase 126. Phenylalanine is toxic to the developing brain. Using the following schematic, propose a suggestion to alleviate the problems associated with Phenylketonuria. Non-competitive inhibition of acetylcholinesterase 127. Alkaline phosphatase is produced by bone and liver in the human body. The amount of alkaline phosphatase in blood can help identify if a patient potentially has certain types of bone and/or liver-related disease, including Paget disease, hepatitis, and certain types of cancer. The optimal pH range for alkaline phosphatase activity is a pH of 8.0 to 10.0. What happens to the activity of the alkaline phosphatase at a pH of 2.0? Significantly decreases 128. In the reaction provided below, glucose-6-phosphate accumulates in the cell and binds to hexokinase at a site that is distinct from the active site. This prevents hexokinase from binding to its substrate. What happens to the amount of glucose in the cell once hexokinase is inhibited? Increases 129. In the reaction provided below, glucose-6-phosphate accumulates in the cell and binds to hexokinase at a site that is distinct from the active site. This prevents hexokinase from binding to its substrate. What type of inhibition is occurring in this example (utilize the figure from 128) Non-competitive inhibition 130. Patients with chronic mylogenous leukemia (CML) have a mutation that results in the production of BCRABL, an enzyme that speeds up cell division using ATP as a substrate. The drug Gleevec impairs the activity of the enzyme. Using the illustrations of the enzyme above, what best describes how the drug exerts its effect? Gleevec is a competitive inhibitor and prevents ATP from binding with the active site of the enzyme. 131. Below is a schematic showing the synthesis and degradation of acetylcholine, an important neurotransmitter. If you were to design a drug to keep the acetylcholine concentration high, where would you target a drug inhibitor? Acetylcholinesterase 132. In the figure provided below, what component of the enzymatic cycle does the number 3 depict? Enzyme-Product Complex 133. What happens to the enzyme at the end of the cycle? The enzyme is used again. The enzyme will bind to a substrate. 134. The concept of the induced fit applies to which part of the enzymatic cycle? Enzyme-Substrate Complex 135. Inhibitors that have a similar structure to a substrate of an enzyme are most likely to bind to the enzyme’s ____________ and be a ____________ inhibitor. Active site, Competitive 136. When an inhibitor binds reversibly to a site of the enzyme that is not the active site, what type of inhibition results? Non-competitive 137. You are in charge of designing a drug that inhibits the activity of a specific enzyme. An important criteria for the drug selection is to ensure that the drug directly competes with the original substrate by binding to the active site of the enzyme. Which of the following kind of inhibitor would be an ideal choice? Competitive inhibitor 138. One way a cell can avoid overproduction of a molecule is by using a particular type of inhibition in which this same molecule acts as an inhibitor for an enzyme in its production pathway. This type of regulation is known as ___________ inhibition. Feedback 139. Identify the components for each letter in the diagram provided below. A) Enzyme-Substrate Complex; B) Products; C) Substrate; D) Enzyme-Product Complex; E) Enzyme 140. What type of inhibition is shown in the image provided to the right? Non-competitive 141. What are differences difference between competitive and non-competitive inhibitors? Competitive inhibitors bind reversibly to the active site and do not change the enzyme tertiary structure; noncompetitive inhibitors bind reversibly or irreversibly to the allosteric site and change the enzyme tertiary structure. 142. Which of the following statements accurately describes cooperativity? Hemoglobin can bind subsequent molecules of oxygen more easily after the first oxygen molecule binds. 143. Patients with carbon monoxide (CO) poisoning may exhibit pink or cherry red skin, mucus membranes and nails. Which statement accurately describes hemoglobin's role in CO poisoning? Hb binds to CO with a higher affinity than oxygen and stabilizes the R-state. 144. Hemoglobin and myoglobin proteins bind molecular oxygen. The protein subunit of hemoglobin does not bind directly to the oxygen. Instead, a specific atom binds oxygen. In hemoglobin, which of the following will directly bind oxygen? Iron 145. The structure of fetal hemoglobin allows it to have a higher affinity for oxygen when compared to maternal hemoglobin. Which of the following accurately describes fetal hemoglobin? Binds oxygen tightly at lower oxygen concentrations 146. In which of the following patients is the planar conformation of the heme group in hemoglobin favored? In a firefighter who is brought to the emergency room after entering a burning building 147. Myoglobin stores oxygen, whereas hemoglobin transports oxygen. Which of the following statements accurately describes the affinity of myoglobin and hemoglobin for oxygen? Myoglobin has a higher affinity for oxygen compared to hemoglobin 148. Hemoglobin transports oxygen and myoglobin stores oxygen. They exhibit different oxygen binding curves when plotted on a graph with total partial pressure of the oxygen (x-axis) plotted against the percent saturation of hemoglobin (y-axis). What is the shape of the oxygen binding curves for hemoglobin and myoglobin? Hemoglobin has a sigmoidal curve, whereas myoglobin has a hyperbolic curve 149. Based on the graph (shown below), 50% of Hemoglobin is saturated with oxygen at approximately _________ torr and ______________% of myoglobin is saturated with oxygen at the same concentration. 28, 90% 150. Which of the following favor the oxygenated form of hemoglobin? (select all that apply) Planar heme group; Relaxed state; high pH; subunits are closer together 151. Which of the following does not bind directly to hemoglobin? CO2 152. Which of the following components can bind directly to the iron atom in hemoglobin? (select all that apply) Oxygen & CO 153. Acidosis occurs as a result of cardiac arrest. Which of the following is the theoretical reason why sodium bicarbonate might be administered to your patient during a cardiac arrest? The bicarbonate acts to increase pH, which may allow hemoglobin to transport oxygen more efficiently 154. Myoglobin and hemoglobin each have different numbers of subunits and this affects their respective oxygen storage and delivery capabilities. How many subunits does myoglobin have versus hemoglobin? One, Four 155. Patients with sickle cell anemia have atypical hemoglobin, which will distort the red blood cells into sickle shape during oxygen delivery. The substitution of a hydrophilic amino acid with a ____________amino acid in hemoglobin subunits results in the polymerization of hemoglobin, leading to the sickling of red blood cells. Hydrophobic 156. Carbonic anhydrase is an important __________ present in the red blood cells that aids in efficient transportation of carbon dioxide in the form of _________, from tissues to lungs. Enzyme, bicarbonate ions 157. Hemoglobin acts as a buffer and controls the pH of the blood by binding _______. H+ ions 158. Carbon monoxide outcompetes oxygen for attachment to the __________ group of hemoglobin where it is permanently, covalently attached. Heme 159. What is the number of oxygen molecules that must bind in order for hemoglobin to shift to the R–state (relaxed state)? 1 160. Does oxygenated hemoglobin have a high or low affinity for carbon monoxide (CO)? High affinity for CO 161. What happens to oxygenated hemoglobin as the amount of CO2 increases? pH decreases, Hb shifts more to the T state, oxygen affinity decreases 162. Tissues at rest have an oxygen concentration of 40 Torr. What is the fraction of hemoglobin with oxygen bound (hemoglobin saturation) at 40 torr and at pH 7.2? 0.5 163. Which statement describes the relationship between the pH in the lungs and peripheral tissues? Relative to the lungs, the pH in the peripheral tissues is lower because the CO2 generated by metabolism is converted to bicarbonate, which releases protons (H+) 164. Which of the following statements are true? (Choose all that apply) As pH decreases, hemoglobin's affinity for oxygen decreases. & As 2,3-BPG decreases, hemoglobin's affinity for oxygen increases. 165. Gas exchange between maternal blood and fetal blood takes place in the placenta. If curve c in the following graph represents the dissociation curve of adult hemoglobin, which curve would represent the dissociation curve of fetal hemoglobin? Curve B 166. Why is more oxygen unloaded from hemoglobin in an actively metabolizing tissue than in a resting tissue, even at the same concentration of O2? At the lower pH of an actively metabolizing tissue, hemoglobin has a lower affinity for oxygen. 167. Acidosis occurs as a result of cardiac arrest. Which of the following is the theoretical reason why sodium bicarbonate might be administered to your patient during a cardiac arrest? The bicarbonate acts to increase pH, which may allow hemoglobin to transport oxygen more efficiently. 168. Hemoglobin acts as a buffer and controls the pH of the blood by binding to __________. H+ ions 169. Due to the Bohr effect, how will the curve below shift in response to changes in pH? An increase in H+ concentration will shift hemoglobin's oxygen-binding curve to the right, while a decrease in H+ concentration will shift the curve to the left. 170.